The present invention relates to a production control system for product development, acceptance of an order, material arrangement, assembly operations and the like in product manufacture. The present invention also relates to a production control technique which is directed to large variety individual production rather than large variety mass production, and which can minimize stock of finished products.
In a conventional system for development, production and sales of products, models having a standard specification have been set based on market needs, and the development has been carried out for the respective models. The production mode is speculative production, which is based on the sales performance or the past market trend for similar models. If the demand forecast is different from the actual market demand, the stock of finished products increases or lack of stock occurs. Production plans have required elaborate modification, and directions for material procurement have been reconsidered whenever needed.
Products except for models having a standard specification have been required to be customized, which needs particular product design. Most of customized products can be provided by modifying a standard specification, wherein, on the basis of the standard specification, addition of parts or elimination of unnecessary parts is made so as to adapt to the customized specification. The addition of parts or the elimination of unnecessary parts has required a designer""s determination for customized specifications whenever accepting orders. Arrangement of untypical parts or directions for untypical manufacturing operations for adaptation to a customized product specification requires the presence of a person in charge of flow control in production for respective customized products.
A conventional production system has been disclosed in, e.g., JP-B-77432. In FIG. 9 is shown a block diagram of the entire production system for retail goods of the conventional production system. As shown in this figure, the system comprises a retail sales information collecting means 100, a production size setting means 120, a directing means for direction the preparation and production of raw material 130 and a production means 140.
The retail sales information collecting means 100 includes POS terminals installed at different retail outlets and public networks 110 for correcting the POS terminals to a host computer. The production size setting means 120 includes a scale-up estimating routine 150, a demand forecast routine 160 and a production size determining routine 170. The scale-up estimating routine 150 receives sales information from the POS terminals through the public networks 110 as input data at any time. The scale-up estimating routine 150, which calculates a scale-up estimate based on the sales information, is connected to the demand forecast routine 160, where demand forecast is carried out based on the scale-up estimates for respective products forwarded by the scale-up estimating routine 150. The final sales estimates thus obtained at the demand forecast routine 160 are forwarded to the production size determining routine 170 connected to the demand forecast routine 160. The required size of additional production thus determined is forwarded to a raw material procurement routine 190 and the control unit 141 of the production means 140 simultaneously through the directing means 130 for production. Whenever the production at the production means 140 is completed, the inventory data and the additional production data in an inventory data table 171 are timely updated to be used as new data.
Such a conventional production system has created the following problems.
Actual sales results could be against a determined production plan because of speculative production according to the demand forecast estimated from the sales information. In such a case, the stock of finished products increases to cause loss in warehouse administrative and maintenance expense, or the delivery time required by a customer can not be met, leading to failure to accept an order.
In factory production, a relevant department draws up a production plan to increase the efficiency of its own department. This can cause the term from acceptance of an order placed by a customer to the delivery of the ordered product to be extended, the stock of unfinished products to increase, or to increase the number of persons in charge of modification and design of the production plan.
In addition, the specifications required by customers have greatly diversified, causing speculative production to become impossible. This could cause the delivery time for the ordered specifications to extend or required delivery not to be met, leading to failure to accept the order.
It is an object of the present invention to eliminate these problems and to provide a production control system capable of preventing the stock of products from increasing or lacking when actual sales results are against demand forecast for speculative production, avoiding failure to accept an order because of unmet delivery time, meeting the delivery time requested by a customer without stock of finished products by producing products with the specifications required by the client met in the ordered number, directly reflecting information of customers"" orders on production, and sharing necessary information among a customer, a factory and a parts manufacturer to improve the efficiency from acceptance of an order to production.
It is another object of the present invention to provide a production control system for air conditioners wherein an air conditioner is divided into functional blocks, and large variety of customized products can be produced in a short period of time by selectively combining function blocks in accordance with customers"" requirements.
It is another object of the present invention to provide a method for producing air conditioners, wherein information on an ordered specification for an air conditioner, which is inputted by a customer, can be processed and administrated on line through a computer to effectively produce the product required by the customer in a short period of time.
According to a first aspect of the present invention, there is provided a production control system comprising an order acceptance management means for determining a customized product based on a customized specification and a delivery time of the customized product input by a customer through a screen, the order acceptance managing means including a routine for preparing a menu-driven specification, which produces the customized specification selected by the customer based on a menu table; a menu-driven production control means for providing required directions on material procurement, inventory management, manufacturing line control and physical distribution based on the customized specification, and for carrying out planned control based on production data; and a customer management means for supporting delivery and maintenance of the product based on data on order acceptance given by the order acceptance management means; wherein operations from order acceptance to material procurement and directions for production can be dealt with on line, and data on the product ordered by the customer are shared between the customer and a manufacturer of the product.
In the production control system according to the first aspect, the screen may show at least one of a perspective view and a menu table of functional blocks, into which the customized product is divided in terms of function.
In the production control system according to the first aspect, the menu table may be modified or updated based on market needs, in terms of, e.g., a standard specification and a plurality of optional specifications.
In the production control system according to the first aspect, the menu table may include a standard specification and a plurality of specifications in respective functional blocks, the product being divided into the functional blocks in terms of functions so that the functional blocks are coupled and combined in accordance with criteria of certain positions and connecting devices to perform certain functions.
The production control system according to the first aspect may further comprise a production seat producing means for producing production seats in a number corresponding to an acceptable production schedule found based on an estimated number of products to be produced in consideration of demand size forecast, estimated man-hours for production and assembly capacity of a production process; and a production seat management means for collating production man-hours required for production according to the delivery time of the customized product with an unoccupied state in a seat table corresponding to the production schedule to finalize the delivery time.
In the production control system according to the first aspect, the menu-driven production control means may comprise a requirement calculation routine for reading out, based on product constitution of the customized product, production arrangement data of constituting elements of the customized product from manufacturing practice data with drawing data, production data and parts procurement data included therein; an operation direction producing routine for producing data on procedure and guidelines for assembly of the customized product based on product specification data from a memory for storing data on order acceptance and the manufacturing practice data; and a physical distribution control means for providing delivery directions for shipment of a finished product based on data on the delivery time and a receiver stored on the memory for storing data on order acceptance, and data on production progress.
In the production control system according to the first aspect, the customized specification may be input to the order acceptance management means from the customer through a public communication network, wireless communication or satellite communication.
In the production control system according to the first aspect, parts arrangement may be carried out from a factory to a parts manufacturer through an EDI communication network.
In the production control system according to the first aspect, the order acceptance management means and the menu-driven production control means may be connected to the customer management routine, a material procurement and inventory management means, a manufacturing line control means and a physical distribution control means through at least a communication line.
According to a second aspect of the present invention, there is provided a method for producing an air conditioner, which is divided into at least a heat source block for a refrigeration cycle, a driving block for a heat medium circulation in the refrigeration cycle, and a circulation connecting block for the refrigeration cycle, comprising the steps of providing an order acceptance management means for determining a customized product by selection among a standard specification and a plurality of optional specifications held with respect to the respective blocks; and providing a menu-driven production control means for providing required directions on material procurement, inventory management, manufacturing line control and physical distribution based on the customized specification and a delivery time of the customized product, and carrying out planned control based on production data; wherein operations from order acceptance to material procurement and directions for assembly can be dealt with on line.
According to a third aspect of the present invention, there is provided a method for producing an air conditioner, which comprises a compressor, a condenser, an expansion device and an evaporator, comprising the steps of providing a standard specification and a plurality of optional specifications with regard to respective functional blocks, into which the air conditioner is divided in terms of functions; producing a specification of a customized product based on specification data determined for the respective functional blocks; and managing production seats corresponding to production schedule for the specification of the customized product based on material procurement data and man-hours for production for the respective functional blocks.